Echocardiographic features of post−transcatheter aortic valve implantation thrombosis and endocarditis

Background: Transcatheter heart valve thrombosis (THV-t) and endocarditis (THV-e) are relevant complications after transcatheter aortic valve implantation (TAVI). Transcatheter heart valve (THV) dysfunction definition is mostly based on Doppler (stenosis/regurgitation) without considering leaflets characteristics. Purpose: To evaluate the additional diagnostic value of leaflets echocardiographic features over Doppler when prosthetic valve complication is suspected. Methods: Among 621 post-TAVI patients, 128 cases with probable valve complication were identified. THV-t was finally diagnosed in 13 patients (10%) and THV-e in 8 (6%), while the remaining 107 (84%) had no definitive diagnosis of thrombosis/endocarditis (THV-no). We analyzed at 2 time points (baseline and follow-up) both traditional Doppler parameters and leaflets morpho-functional features. Results: Both Doppler and leaflets parameters showed high sensitivity (sensitivity 92%) and low specificity (ranging from specificity 32% to 74%) in detecting THV-t. Interestingly, the combination of mean aortic pressure gradient ≥20 mm Hg and leaflet thickening significantly improved the specificity of echocardiography for diagnosis of THV thrombosis (specificity 94%). On the other hand, echocardiographic diagnosis of THV endocarditis remained limited by very low sensitivity despite showing high specificity. Conclusions: The combination of Doppler and leaflets parameters can improve the echocardiographic diagnosis of THV thrombosis in post-TAVI patients with suspicious symptoms, via a significant increase in the overall test specificity. This would potentially allow more rational gatekeeping to more expensive/invasive diagnostic examinations (eg, CT scan) or therapeutic trials (eg, unnecessary anticoagulation).